Page 583 - Veterinary Immunology, 10th Edition

and IL-33 from epithelial cells (Fig. 19.3). ILC2 cells are required for
VetBooks.ir the development of early innate immunity to parasitic helminths as

well as regulating some type 2 inflammatory responses such as
asthma and allergic disease (Chapter 30). They play a key role in

regulating type 2 immunity by acting on macrophages, mast cells,
and eosinophils. Thus they control eosinophil production and
induce an eosinophila. They also induce mucus production by
goblet cells, alternative activation of macrophages, and tissue

repair. ILC2s can be readily converted into ILC1s by IL-12, and this
can be reversed by IL-4.

FIG. 19.3 The role of Group 2 innate lymphoid cells. Activated by
the presence of intestinal helminths and mast cell products, they
generate type 2 cytokines and hence stimulate both eosinophil and
IgA production. They can be considered functional partners of Th2
cells.

Group 3 ILCs

Group 3 ILCs are found in the gastrointestinal tract (lamina propria,
tonsils, Peyer's patches, and appendix) as well as in the lung. They

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